One of the pivotal events in adolescents' lives is engaging in sexual activity. Based on previous correlational studies, ethnic and low income adolescents are often identified as at-risk for early sexual activity which often results in pregnancy and/or sexually transmitted diseases (STDs). Yet these findings fail to explain the day-to-day context in which adolescents become sexually active, and thus little is known about factors that influence adolescents to have intercourse for the first time. We do not know whether adolescent girls choose to become sexually active or whether they do so reluctantly or unwillingly. This study will address the research question "What factors influence adolescent girls to engage in sexual intercourse?" The ethnographic method will be used to explore, identify, examine, and describe adolescent girls' sexual behavior within the context of their day-to-day lives. It is anticipated that the findings will have implications for theoretical practical values in promoting fuller understanding of the phenomenon, thus leading to the eventual planning and implementation of effective nursing intervention to decrease adolescent pregnancy and STDs rates.